New York Gov. Andrew Cuomo, left, listens Friday as New Jersey Gov. Chris Christie talks at a news conference in New York. The governors announced a mandatory quarantine for people returning to the United States through airports in New York and New Jersey who are deemed to be at "high risk" for Ebola. Mark Lennihan/AP hide caption

itoggle caption Mark Lennihan/AP

Patient Nina Pham is hugged by Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, outside of the National Institutes of Health in Bethesda, Md., on Friday. Pham was discharged after testing free of Ebola. Pablo Martinez Monsivais/AP hide caption

itoggle caption Pablo Martinez Monsivais/AP

The media is all over this story: Ebola in NYC! Don Weiss, a doctor with the New York City Health Department, faces microphones outside the bowling alley visited by the physician who tested positive for the virus. John Minchillo/AP hide caption

itoggle caption John Minchillo/AP

Data sources: David Ropeik/Harvard University, National Weather Service, World Health Organization, Northeastern University Laboratory for the Modeling of Biological and Socio-Technical Systems, National Geographic, United States Census Adam Cole and Ryan Kellman/NPR hide caption

itoggle caption Adam Cole and Ryan Kellman/NPR

At the onset of symptoms, Dr. Adaora Igonoh (center) and her colleagues began drinking oral rehydration solution. It doesn't taste great but they say it helped them survive Ebola. They each downed over a gallon a day for nearly a week. Andrew Esiebo/Courtesy of WHO hide caption

itoggle caption Andrew Esiebo/Courtesy of WHO

A rogues gallery of the viruses (left to right) that cause MERS, SARS, and influenza. Niaid; 3D4Medical; Niaid/Science Source hide caption

itoggle caption Niaid; 3D4Medical; Niaid/Science Source